Vision impairment studies

Problems with eyes and vision are common in people with ME/CFS, but scientific investigations have been few. To redress the balance, ME Research UK and the Irish ME Trust funded the Vision and Language Research Group, University of Leicester to undertake experiments to identify and quantify vision-related symptoms in the disease and, to date, the researchers have published several scientific papers reporting a range of visual impairments. In two robust scientific papers, the group at the University of Leicester has shown, first, that ME/CFS patients perform worse than matched controls across three specific aspects of vision; and, second, that eye movement dysfunction is a prominent feature. In a third study, they used the new DePaul Symptom Questionnaire to quantify the vision-related symptoms, finding that most ME/CFS patients had some degree of sensitivity to bright lights, were unable to focus vision and/or attention, and experienced eye pain.

Rachel Wilson, an MPhil student in the Leicester Department, has just completed her thesis on the subject, and the full text (pdf; 176 pages) can now be downloaded. The abstract is given below, and in her acknowledgements, Rachel says, “I would also like thank the ME/CFS community for their kind support throughout the project. Without this, the project would not have been possible. I am especially thankful to the patients who gave up their time to make the journey to Leicester, whom I have had the genuine pleasure to work with. I would also like to thank ME Research UK for providing the studentship in order to carry out the project, and to the School of Psychology for funding my masters.” The work from part of her thesis was recently published (read more), and further publications are expected.

Abstract

ME/CFS is a debilitating disorder affecting at least 250,000 people in the United Kingdom. This condition has a number of incapacitating symptoms including post-exertional fatigue, cognitive deficits, and flu-like symptoms. However, with an unresolved aetiology, controversial diagnosis, and no clear treatment, it is important that potential clinical features are identified and explored.

Visual symptoms are often reported by patients, and, there is now a growing body of literature to experimentally support this. Nevertheless, there is a paucity of research investigating precisely how these visual symptoms impact the everyday lives for those with ME/CFS. This is especially the case for reading activities. The aim of the experiments within this thesis was to thoroughly investigate vision-related reading in ME/CFS patients.

The results show that vision related reading discomfort in ME/CFS is unlikely to be a function of impaired ocular motor function in reading or a poorer reading acuity. However, ME/CFS patients did demonstrate elevated levels of pattern-related visual stress. Given that text is spatially reflective of patterned stimuli that can induce visual stress distortions in those who are susceptible, this may account for some of the visual symptoms that are experienced during reading in those with ME/CFS. These findings are discussed in relation to possible therapeutic interventions and it is suggested that future, more direct, research is required in order to augment the findings.